Answer: C . 
and 
Step-by-step explanation:
Definition:
Null hypothesis
is a statement about the population parameter according to the objective raised by the researcher . It contains '=' , '≤' and '≥' signs.
Alternative hypothesis
is also a statement about the population parameter but against null hypothesis . It contains '≠' , '<' and '>' signs.
Let 
be the average customer waiting time for the population.
Given : The average customer waiting time at a fast food restaurant has been 7.5 minutes.
Objective of test : After using new system , the average customer waiting time is at least 7.5 or less than 7.5.
Then, the null and alternative hypothesis for this scenario will be :
Answer: Mood
Step-by-step explanation: It would be mood because when you put it in a sentence it makes the most sense.
Example Sentence: The atmosphere of the room is sad.
The mood of the room is sad.
The other answers don't make as much sense. Hope this helps!
Note:xy means x times y and x(y) means the same thing
so
first we get rid of square root then
make the equation equal to zero becaues if
xy=0 then x or/and y=0
squareroot(y-1)+3=y
isolate the squareroot
subtrac 3 from boht sides
squareroot(y-1)=y-3
square both sides (since they are equal, you should be able to square both sides and still make it true)
(squareroot(y-1))^2=(y-3)^2
(y-1)=(y-3)(y-3)
y-1=y^2-6y+9
subtrac y from both sides
-1=y^2-7y+9
add 1 to both sides
0=y^2-7y+10
find what two number multiply to make 10 and add to get -7
the answer is -2 and -5
0=(y-5)(y-2)
therfore
y-5=0
and/or
y-2=0
therefor
y=5 or/and 2 might work
let's try out 2
square root(2-1)+3=2
square root(1)+3=2
1+3=2
false
so 2 doesn't work
let's try 5
squareroot(5-1)+3=5
squareroot(4)+3=5
2+3=5
5=5
true
y=5
X + x+1 + x+2 + x+3 + x+4 = 110
5x +10 = 110
5x = 100
x = 20
The numbers are
20 21 22 23 and 24
X^2-9x=-8
x^2-9x+8=-8+8
x^2-9x+8=0
(x-8)(x-1)=0
x-8=0
x-8+8=0+8
x=8
x-1=0
x-1+1=0+1
x=1
There are 2 solutions, which are 1 and 8
